We identify the impact of local firm concentration on incumbent performance with a quasi natural experiment. When Germany was divided after World War II, many firms in the machine tool industry fled the Soviet occupied zone to prevent expropriation. We show that the regional location decisions...

Instrumental variables (IV) are a common means to identify treatment effects. But standard IV methods do not allow us to unpack the complex treatment effects that arise when a treatment and its outcome together cause a second outcome of interest. For example, IV methods have been used to show...

Using newly-constructed spatially-disaggregated data for London from 1801-1921, we show that the invention of the steam railway led to the first large-scale separation of workplace and residence. We show that a class of quantitative urban models is remarkably successful in explaining this...

Shale gas has grown to become a major new source of energy in countries around the globe. While its importance for energy supply is well recognized, there has also been public concern over potential risks such as damage to buildings and contamination of water supplies caused by geological...

We identify the causal effect of trade-integration with China and Eastern Europe on voting in Germany from 1987 to 2009. Looking at the entire political spectrum, we find that only extreme-right parties respond significantly to trade integration. Their vote share increases with import...

This paper studies the role of leaders in the social movement against slavery that culminated in the U.S. Civil War. Our analysis is organized around a natural experiment: leaders of the failed German revolution of 1848-49 were expelled to the U.S. and became anti-slavery campaigners who helped...

This article reviews recent literature using insights from history to answer central questions in urban economics. This area of research has seen rapid growth in the past decade, thanks to new technologies that have made available increasingly rich data stretching far back in time. The focus is...